class CPU {
    double price;
    // 嵌套类
    class Processor{

        //嵌套类的成员
        double cores;
        String manufacturer;

        double getCache(){
            return 4.3;
        }
    }

    //嵌套受保护的类
    protected class RAM{

        //受保护的嵌套类的成员
        double memory;
        String manufacturer;

        double getClockSpeed(){
            return 5.5;
        }
    }
}